The proposed studies will assess the effect of psychological disturbance on several aspects of humoral and cellular immunity. Based on previous research showing altered immune responses in infant and juvenile primates, we propose to conduct a detailed characterization of macrophage function in young squirrel monkeys following two different types of separation from the mother. Phenotypic aspects of macrophages will be examined using: (1) surface morphology and nonspecific esterase staining, and (2) immunochemical techniques that utilize monoclonal antibodies directed against macrophage surface proteins. Functional capabilities of macrophages from control and stressed subjects will be compared by measuring (1) phagocytosis and intracellular killing, (2) antibody dependent cytolitic events, and (3) support and regulation of T lymphocyte functions. A second series of studies will compare the effect of acute psychological disturbance on T cell subsets in juvenile monkeys of two species, the squirrel monkey and rhesus macaque. The comparison is based on prior demonstrations of significant species differences in endocrine and immune responses, and will evaluate the influence of temporal factors, activity patterns, and the effect of providing social companions. Pharmacological manipulation of the pituitary-adrenal axis will also be employed to evaluate the role of cortisol in mediating the shifts in circulating levels of T lymphocytes. The third area of research is concerned with the impact of psychological disturbance during pregnancy on the ontogeny of infant immunity. The influence of female social status and relocation during pregnancy will be assessed by monitoring the differential transmission of IgG to newborn infants. IgG levels will be examined during the first 3 months of infant development, and the capacity of the infants to mount an antibody response to antigen challenge will be determined. The antigens we will use are the bacteriophage (OX174) and tetanus toxoid (TT) to assess the significance of psychoendocrine activity during pregnancy and the resulting alterations in the transmission of maternal antibody. We have already established the efficacy of both antigens and assay methods in previous research on nonhuman primates.